/Engine/Source/Runtime/Engine/Classes/Materials/MaterialExpressionNamedReroute.h
Find a variable declaration in the entire graph
null if not found
[UMaterialExpressionNamedRerouteDeclaration](API\Runtime\Engine\Materials\UMaterialExpressionNamedRerouteD-) * FindDeclarationInMaterial ( const [FGuid](API\Runtime\Core\Misc\FGuid) & VariableGuid ) const